Their server browser whole thing is being upgraded in the next game update with community XP on the servers , lets see what happens on that first
Right if you havent played the original Insurgency or their WW2 game Day of Infamy , you will have a hard time to master it all.
If you are new to game id suggest to play "Local play" against bots and try out the different roles etc, commanders and radiomen need to be beside eachother for airstrikes
There is pop up tutorials on the right of your screen in game too if it detects your new to the role.
Sandstorm just isnt the type of game to hop on and play straight away, but if your up for a challenge go for it ?
Mess around on local play with insurgents and security to find out their advantages and how to counter each other is the main thing.